Examples

Student-Step Rollup Example

This example demonstrates how DataShop calculates step start time, step end time, step duration,
and correct step duration for a student on a series of steps.

To follow the example, refer to the timeline representation of steps and the table of calculated times (both below),
and the definitions of student-step rollup fields. Note that steps alternately appear
above and below the gray line to improve the readability of the example.

Step #

Start Time

End Time

Step Duration (sec)

Correct Step Duration (sec)

Notes

11

15:32

15:42

10

null

A problem event precedes the first
transaction for the step. DataShop uses the problem event time as the step start
time. The step end time is the time of the last attempt on the step. No attempt is
correct for this step, so the sum of the durations is the total length of time spent on
the step, and there is no Correct Step Duration.

12

15:45

15:49

4

null

A problem event signifies a new instance of the same problem; it is used as the step start time.
The correct attempt is not the first attempt, so again there is no Correct Step Duration.

2

null

46:00

null

null

No problem event precedes the first attempt for the step and the preceding
transaction is more than 10 minutes before the first transaction on the step. Given this,
DataShop does not calculate a step start time, nor a Step Duration or Correct Step
Duration.

3

46:00

46:05

5

5

No problem event precedes the first attempt, but the preceding transaction's
time is less than 10 minutes prior so it is used as the step start time. Correct Step Duration
and Step Duration are equivalent because the first transaction is a correct attempt.

4

46:06

46:25

4+3+3=10

null

Step 4 is interrupted by attempts toward Step 5. DataShop excludes time spent
toward Step 5 in its calculation of total time spent on Step 4. The step duration
is the sum of the durations for transactions at 46:10 (4s), 46:13 (3s), and 46:25 (3s).

5

46:13

46:22

9

null

No problem event precedes the first attempt, but the preceding transaction's
time is less than 10 minutes prior so it is used as the step start time.

Learning Curve Examples

Error Report Example

Sample Selector

Sample Selector is a tool for creating and editing
samples, or groups of data you compare across—they're
not "samples" in the statistical sense, but more like filters.

By default, a single sample exists: "All Data". With the Sample
Selector, you can create new samples to organize your data.

You can use samples to:

Compare across conditions

Narrow the scope of data analysis to a specific time range,
set of students, problem category, or unit of a curriculum (for example)

A sample is composed of one or more filters, specific
conditions that narrow down your sample.

Creating a sample

The general process for creating a sample is to:

Add a filter from the categories at the left to the composition
area at the right

Modify the filter to select the subset of data you're interested
in, saving it when done

View the sample preview table to see the effect of adding your filter,
making sure you don't have an empty set (ie, a filter or combination
of filters that exclude all transactions).

Name and describe the sample

Decide whether to share the sample with others who can view the
dataset

Save the sample

The effect of multiple filters

DataShop interprets each filter after the first as an additional
restriction on the data that is included in the sample. This is also known
as a logical "AND". You can see the results of multiple filters in the
sample preview as soon as all filters are "saved".